Patch from Robin Kirkham <Robin.Kirkham@mlb.dmt.csiro.au> to distinguish

between CPU32 and CPU32+ cores.  Commentary follows:

    Unfortunately c/src/exec/score/cpu/m68k/m68k.h incorrectly defines
    M68K_HAS_MISALIGNED for the plain old CPU32 (it is correct for the CPU32+).
    As a consequence, the recently-relocated m68k memcpy() may still attempt
    misaligned memory accesses.

    I suggest that until such time as egcs/gcc differentiates these cores
    that we invent a new preprocessor symbol, RTEMS__mcpu32p__ for this
    purpose, on the assumption that egcs may one day grow a -mcpu32+ option
    which will define a __mcpu32p__ symbol (whether this option would also
    define __mcpu32__ is yet to be resolved).

    BSPs that have a CPU32+ (like gen68360) would for the time being define
    RTEMS__mcpu32p__ using -D. The symbol is `RTEMS__mcpu32p__' because
    symbols of the form __xxx__ should only be defined by the compiler
    itself.

    Note that the patch tests for RTEMS__mcpu32p__ *before* __mcpu32__, since
    __mcpu32__ is still defined for the CPU32+. It does not change the
    gen68360 BSP.

    An aside:
    Note that in egcs-1.0.3a, the option -m68332 is identical to -mcpu32,
    except it defines __mc68332__ as well as __mcpu32__. This is only
    for the sake of compatibility. The story with -m68302 is similar;
    it defines __mc68302__ and __mc68000__. In my opinion these options
    are depreciated and ought to be avoided in RTEMS.

1 files changed, 18 insertions, 7 deletions

diff --git a/c/src/exec/score/cpu/m68k/m68k.h b/c/src/exec/score/cpu/m68k/m68k.h
index a6d24562d2..1d12e9ea10 100644
--- a/c/src/exec/score/cpu/m68k/m68k.h
+++ b/c/src/exec/score/cpu/m68k/m68k.h
@@ -37,10 +37,20 @@ extern "C" {
  *     -m68040 -msoft-float
  *     -m68040
  *     -m68040 -msoft-float
- *     -m68302        (no FP)
- *     -m68332        (no FP)
+ *     -m68302        (no FP) (deprecated, use -m68000)
+ *     -m68332        (no FP) (deprecated, use -mcpu32)
  *     -mcpu32        (no FP)
  *
+ *  As of gcc 2.8.1 and egcs 1.1, there is no distinction made between
+ *  the CPU32 and CPU32+.  The option -mcpu32 generates code which can
+ *  be run on either core.  RTEMS distinguishes between these two cores
+ *  because they have different alignment rules which impact performance.
+ *  If you are using a CPU32+, then the symbol RTEMS__mcpu32p__ should
+ *  be defined in your custom file (see make/custom/gen68360.cfg for an
+ *  example of how to do this.  If gcc ever distinguishes between these
+ *  two cores, then RTEMS__mcpu32p__ usage will be replaced with the
+ *  appropriate compiler defined predefine.
+ *
  *  Here is some information on the 040 variants (courtesy of Doug McBride,
  *  mcbride@rodin.colorado.edu):
  *
@@ -129,27 +139,28 @@ extern "C" {
 #define M68K_HAS_FPU             0
 #define M68K_HAS_FPSP_PACKAGE    0
 
-#elif defined(__mc68332__)
+  /* gcc and egcs do not distinguish between CPU32 and CPU32+ */
+#elif defined(RTEMS__mcpu32p__)
  
-#define CPU_MODEL_NAME          "mcpu32"
+#define CPU_MODEL_NAME          "mcpu32+"
 #define M68K_HAS_VBR             1
 #define M68K_HAS_SEPARATE_STACKS 0
 #define M68K_HAS_BFFFO           0
 #define M68K_HAS_PREINDEXING     1
 #define M68K_HAS_EXTB_L          1
-#define M68K_HAS_MISALIGNED      0
+#define M68K_HAS_MISALIGNED      1
 #define M68K_HAS_FPU             0
 #define M68K_HAS_FPSP_PACKAGE    0
 
 #elif defined(__mcpu32__)
  
-#define CPU_MODEL_NAME          "mcpu32+"
+#define CPU_MODEL_NAME          "mcpu32"
 #define M68K_HAS_VBR             1
 #define M68K_HAS_SEPARATE_STACKS 0
 #define M68K_HAS_BFFFO           0
 #define M68K_HAS_PREINDEXING     1
 #define M68K_HAS_EXTB_L          1
-#define M68K_HAS_MISALIGNED      1
+#define M68K_HAS_MISALIGNED      0
 #define M68K_HAS_FPU             0
 #define M68K_HAS_FPSP_PACKAGE    0